Drive mode switch control device and drive mode switch control method

ABSTRACT

A drive mode switch control device acquires operation information. The drive mode switch control device switches a drive state among at least an autonomous drive state, a manual drive state, and a coordination drive state. The operation detection unit detects a first operation and a second operation based on the operation information when the drive state is not in the manual drive state. The second operation is the drive operation different from the first operation and input after the input of the first operation. The drive mode switch control device switches the drive state from the autonomous drive state to the coordination drive state based on a detection determination of the first operation. The drive mode switch control device switches the drive state from the coordination drive state to the manual drive state based on a detection determination of the first operation.

CROSS REFERENCE TO RELATED APPLICATIONS

The present application is a continuation application of U.S. patentapplication Ser. No. 16/431,824 filed on Jun. 5, 2019, which is acontinuation application of International Patent Application No.PCT/JP2017/036570 filed on Oct. 10, 2017, which designated the UnitedStates and claims the benefit of priority from Japanese PatentApplication No. 2016-237834 filed on Dec. 7, 2016. The entiredisclosures of all of the above applications are incorporated herein byreference.

TECHNICAL FIELD

The disclosure of this specification relates to a drive mode switchcontrol device and a drive mode switch control method each of whichcontrols a drive mode switch between a driver and an autonomous drivefunction.

BACKGROUND

In recent years, development of a vehicle provided with an autonomousdrive function capable of executing a drive operation of the vehicleinstead of a driver has been promoted. In such vehicles, a drive modeswitch between the driver and the autonomous drive function is executed.For example, the drive mode switch from the autonomous drive function tothe driver is executed when the driver performs a drive operation in acase where the vehicle is not in a manual drive mode.

SUMMARY

A drive mode switch control device may acquire operation information.The drive mode switch control device may switch a drive state among atleast an autonomous drive state, a manual drive state, and acoordination drive state. The drive mode switch control device maydetect a first operation and a second operation based on the operationinformation when the drive state is not in the manual drive state.

BRIEF DESCRIPTION OF DRAWINGS

The above and other objects, features and advantages of the presentdisclosure will become more apparent from the following detaileddescription made with reference to the accompanying drawings. In thedrawings:

FIG. 1 is a block diagram showing an overview of a configuration relatedto an autonomous drive mounted on a vehicle;

FIG. 2 is a diagram showing an example of a specific configuration of anautonomous driving ECU, an HCU, and a vehicle control ECU;

FIG. 3 is a state transition diagram showing an overview of a drive modetransition executed by a drive mode switch control unit;

FIG. 4 is a time chart showing a transition when a drive mode switch isexecuted by an override;

FIG. 5 is a time chart showing a transition when the drive mode switchis executed by a handover;

FIG. 6 is a flowchart showing details of a drive mode switch controlprocessing for realizing the drive mode switch by the override;

FIG. 7 is a flowchart showing details of a drive mode switch controlprocessing for realizing the drive mode switch by the handover;

FIG. 8 is a time chart showing a transition when the drive mode switchis executed by the override according to a second embodiment;

FIG. 9 is a flowchart showing details of a drive mode switch controlprocessing for realizing the drive mode switch by the override of FIG.8;

FIG. 10 is a time chart showing a transition when the drive mode switchis executed by the handover according to the second embodiment;

FIG. 11 is a flowchart showing details of a drive mode switch controlprocessing for realizing the drive mode switch by the handover of FIG.10;

FIG. 12 is a block diagram showing an overview of a configurationrelated to an autonomous drive according to a third embodiment;

FIG. 13 is a state transition diagram showing an overview of the drivemode transition executed by a drive mode switch control unit of a thirdembodiment;

FIG. 14 is a time chart showing a transition when the drive mode switchis executed by the override according to the third embodiment; and

FIG. 15 is a time chart showing a transition when the drive mode switchis executed by the override according to a fourth embodiment.

DETAILED DESCRIPTION

For example, as a technique related to a drive mode switch, anautonomous drive vehicle system is disclosed. In the autonomous drivevehicle system includes a drive state switch unit that switches a drivestate of the vehicle among an autonomous drive state, a manual drivestate, and a coordination drive mode. In the autonomous drive vehiclesystem, in a case where the vehicle is in the autonomous drive state,the vehicle switches the drive mode to the coordination drive mode whenan operation amount becomes equal to or greater than an interventiondetermination threshold value and a manual drive start threshold value,or a continuation count of the operation becomes equal to or greaterthan a first threshold value and less than a second threshold value.Furthermore, the drive state is switched from the coordination drivemode to the manual drive state when the operation amount becomes equalto or more than the manual drive start threshold value or when theoperation continuation count becomes equal to or higher than the secondthreshold value.

The inventor of the present disclosure has pointed out that in theautonomous drive state in which the autonomous drive function controlsthe traveling of the vehicle, when the situation where the emergencyavoidance is required occurs, the operation input by the driver in ahurry does not reflect driver's intention. Such drive operations of thedriver often do not have an appropriate operation amount. Therefore, theinventor of the present disclosure considered that it is necessary toswitch to the manual drive state in a state where the driver can adjustthe operation amount appropriately with intention.

The vehicle drive system automatically switches the drive state to themanual drive state when the operation amount of the drive operationbecomes greater than the manual drive start threshold value or thecontinuation count becomes greater than the second threshold value. Inthis configuration, the switch to the manual drive mode can be executedbased on a drive operation that has continued a reflective driveoperation having an excessive operation amount without recover of theintention to drive. When the drive mode switch as described above isexecuted, switching to the manual drive mode can be executed in a statewhere the driver's intention cannot be reflected in the drive operation.

An example embodiment provides a drive mode switch control device and adrive mode switch control method each of which is capable of switchingto a manual drive state after a driver can reflect intention to a driveoperation.

In an example embodiment, a drive mode switch control device for avehicle is provided. The vehicle includes an autonomous drive functionthat performs a drive operation instead of a driver. The drive modeswitch control device controls the drive mode switch between the driverand the autonomous drive function. The drive mode switch control deviceincludes an operation information acquisition unit, a drive state switchunit, and an operation detection unit. The operation informationacquisition unit acquires operation information related to the driveoperation input by the driver. The drive state switch unit switches adrive state among at least an autonomous drive state, a manual drivestate, and a coordination drive state. In the autonomous drive state, atravel of the vehicle is controlled by the autonomous drive function. Inthe manual drive state, the travel of the vehicle is controlled by thedriver. In the coordination drive state, the travel of the vehicle iscontrolled by coordinating a control of the autonomous drive functionand the drive operation of the driver. The operation detection unitdetects an input of a first operation and an input of a second operationbased on the operation information when the drive state is not in themanual drive state. The first operation is the drive operation of thedriver. The second operation is the drive operation different from thefirst operation and input after the input of the first operation. Thedrive state switch unit switches the drive state from the autonomousdrive state to the coordination drive state based on a detectiondetermination of the first operation. The drive state switch unitswitches the drive state from the coordination drive state to the manualdrive state based on a detection determination of the second operation.

In another example embodiment, a drive mode switch control method for avehicle is provided. The vehicle includes an autonomous drive functionthat performs a drive operation instead of a driver. The drive modeswitch control method controls the drive mode switch between the driverand the autonomous drive function. The drive mode switch control methodincludes; acquiring operation information related to the drive operationinput by the driver and detecting a first operation, which is the driveoperation of the driver, based on the operation information when a drivestate is not in a manual drive state, in the manual drive state, thedriver controlling a travel of the vehicle; switching the drive state ofthe vehicle from an autonomous drive state to a coordination drive statebased on a detection determination of the first operation, in theautonomous drive state, the autonomous drive function controlling thetravel of the vehicle, in the coordination drive state, the travel ofthe vehicle being controlled by coordinating a control of the autonomousdrive function and the drive operation of the driver; detecting a secondoperation which is the drive operation different from the firstoperation and input after an input of the first operation; and switchingthe drive state from the coordination drive state to the manual drivestate based on a detection determination of the second operation.

In these configurations, when the drive state is not in the manualstate, the first operation and the second operation, which is operatedafter the first operation, are determined. The first operation is thedrive operation that is estimated to have been inputted by the driver ina hurry. The second operation is the drive operation estimated to beperformed after the driver recovers the intention for driving.

With these configurations, when it is determined that the driver inputsthe second operation, the drive mode is switched from the coordinationdrive mode to the manual drive mode. Thus, the switch to the manualdrive state can be prevented when the reflexive drive operation or thecontinuous drive operation without recover of the intention to drive isperformed. On the other hand, when the driver performs the secondoperation after recovering the intention to drive, the switch to themanual drive state is executed based on the input determination of thesecond operation. The switch to the manual drive state can be executedafter the driver becomes in a state that can reflect the intention onthe drive operation.

Hereinafter, a plurality of embodiments will be described with referenceto the drawings. The same reference numerals are assigned to thecorresponding elements in each embodiment, and thus, duplicatedescriptions may be omitted. When configurations are described onlypartly in the respective embodiments, the configurations of theembodiments previously described may be applied to the rest of theconfigurations. Further, not only the combinations of the configurationsexplicitly shown in the description of the respective embodiments, butalso the configurations of the plurality of embodiments can be partiallycombined even when they are not explicitly shown as long as there is nodifficulty in the combination in particular. Unspecified combinations ofthe configurations described in the plurality of embodiments and themodification examples are also disclosed in the following description.

First Embodiment

Functions of a drive mode switch control device according to a firstembodiment of the present disclosure is achieved by an autonomous driveECU (Electronic Control Unit) 50 shown in FIG. 1 and FIG. 2. Theautonomous drive ECU 50 is mounted on a vehicle A together withelectronic control units such as an HCU (HMI(Human Machine Interface)Control Unit) 20, a vehicle control ECU 80, and the like. The autonomousdrive ECU 50, the HCU 20, and the vehicle control ECU 80 are directly orindirectly electrically connected to each other, and can communicatewith each other. The vehicle A has an autonomous drive function by theoperation of the autonomous drive ECU 50 and the vehicle control ECU 80.

The HCU 20 integrally controls acquisition of input information to anoperation system such as a steering switch and information presentationto the driver. The HCU 20 mainly includes a computer having a mainprocessor 21, a graphic processor 22, a RAM 23, a storage medium 24, andan input/output interface 25. The HCU 20 is electrically connected to aplurality of notification devices 10 for notifying the driver of theinformation.

The notification device 10 notifies various kinds of information relatedto the vehicle A to the occupants of the vehicle A including the driverbased on a notification control signal output by the HCU 20. Thenotification device 10 may be preliminary mounted on the vehicle A, ormay be temporarily mounted on the vehicle A by being brought into thevehicle compartment by the occupant of the vehicle A. The notificationdevice 10 includes, for example, a display device 11 that notifies theinformation by display, a speaker device 12 that notifies theinformation by a notification sound, a message voice, or the like.

The HCU 20 has an information acquisition unit 31 and a notificationcontrol unit 32 as functional blocks by causing the processors 21 and 22to execute the notification control program stored in the storage medium24. The information acquisition unit 31 acquires various kinds ofinformation from the autonomous drive ECU 50 and the vehicle control ECU80. The information acquisition unit 31 acquires, for example, switchrequest information for requesting the drive mode switch from theautonomous drive function to the driver.

The notification control unit 32 generates the notification controlsignal to be output to the display device 11 and the speaker device 12based on the information acquired by the information acquisition unit31. The notification control unit 32 controls the informationpresentation by display and sound by outputting the notification controlsignal to the display device 11 and the speaker device 12. Thenotification control unit 32 notifies the driver of taking over thedrive operation from the autonomous drive function using the displaydevice 11 and the speaker device 12 when the switch request informationis acquired by the information acquiring unit 31.

The vehicle control ECU 80 is directly or indirectly electricallyconnected to a vehicle actuator group 90 mounted on the vehicle A. Inaddition, the vehicle control ECU 80 is electrically connected directlyor indirectly to a sensor group that detects the drive operationperformed by the driver. The vehicle actuator group 90 includes, forexample, a throttle actuator of an electronic control throttle, aninjector, a brake actuator, drive and regenerative motor generators, asteering actuator, or the like.

The sensor group includes an accelerator position sensor 44, a brakeoperation amount sensor 45, a steering angle sensor 46, a detectionswitch 47, or the like. The accelerator position sensor 44 detectsstroke amount of the accelerator pedal 14. The brake operation amountsensor 45 is provided by a brake depression force sensor that detectsthe depression force input to the brake pedal 15.

The steering angle sensor 46 detects the rotation angle of the steeringwheel 16. A steering torque sensor that detects a steering torque inputto the steering wheel 16 may be provided instead of the steering anglesensor 46 or together with the steering angle sensor 46. The detectionswitch 47 detects an operation input to a turn signal lever 17. Eachsensor and the switch 47 output the operation information for detectingthe drive operation to the autonomous drive ECU 50 and the vehiclecontrol ECU 80. The accelerator pedal 14, the brake pedal 15, thesteering wheel 16, and the turn signal lever 17 described abovecorrespond to the operation target of the drive operation.

The vehicle control ECU 80 mainly includes a computer having a processor81, a RAM 83, a storage medium 84, an input/output interface 85, and thelike. The processor 81 executes the vehicle control program stored inthe storage medium 84 so that the vehicle control ECU 80 constructs adrive information acquisition unit 80 a and an actuator control unit 80b as functional blocks.

The drive information acquisition unit 80 a is capable of acquiring, asinformation used for behavior control of the vehicle A, drive stateinformation (described later) in addition to the vehicle controlinformation output from the autonomous drive ECU 50 and the operationinformation output from the sensor group. The drive state informationindicates the operation state of the autonomous drive. The actuatorcontrol unit 80 b generates the control signal output from the vehiclecontrol ECU 80 to the vehicle actuator group 90 based on at least apiece of the vehicle control information and the operation informationacquired by the drive information acquisition unit 80 a.

The autonomous drive ECU 50 is electrically connected directly orindirectly to a GNSS receiver 71, a map database 72, a camera unit 73, alidar 74, a millimeter wave radar 75 and the like. The autonomous driveECU 50 acquires information related to the travel environment around thesubject vehicle necessary for the autonomous drive from these devices(71 to 75).

The GNSS (Global Navigation Satellite System) receiver 71 receivespositioning signals from a plurality of artificial satellites. The GNSSreceiver 71 measures the present position of the vehicle A based on thereceived positioning signals. The GNSS receiver 71 sequentially outputsthe measured position information of the vehicle A to the autonomousdrive ECU 50.

The map database 72 is a storage medium storing a large amount of mapdata. The map data includes structural information such as the curvatureof each road, the gradient, and the length of each section, andnon-temporary traffic regulation information such as speed limit andone-way traffic. The map database 72 causes the autonomous drive ECU 50to acquire the map data around the present position of the vehicle A andin the travel direction.

Each of the camera unit 73, the lidar 74, and the millimeter wave radar75 is provided by an autonomous sensor that detects moving object suchas a pedestrian and another vehicle around the vehicle A, and stationaryobject such as a fallen object on the road, a traffic signal, aguardrail, a curbstone, a road sign, a road marking, and a lane marker.The camera unit 73, the lidar 74, and the millimeter wave radar 75sequentially output the detected object information related to thedetected moving object and stationary object to the autonomous drive ECU50.

The camera unit 73 includes a monocular or compound eye front camerathat photographs a front area of the vehicle A, and an image processingunit that analyzes an image of the front area photographed by the frontcamera. The camera unit 73 acquires detected object information byextracting the moving object and the stationary object in the image ofthe front area.

The lidar 74 emits laser light toward the travel direction of thevehicle A, and acquires detected object information by receiving thelaser light reflected by the moving object, the stationary object, orthe like existing in the travel direction. The millimeter wave radar 75emits a millimeter wave toward the travel direction of the vehicle A,and acquires detected object information by receiving the millimeterwave reflected by the moving object, the stationary object, or the likeexisting in the travel direction. The millimeter wave radar 75 candetect an object located farther than the lidar 74 can detect.

The autonomous drive ECU 50 executes the acceleration/decelerationcontrol and the steering control of the vehicle A in cooperation withthe vehicle control ECU 80 so as to exhibit the autonomous drivefunction capable of executing the drive operation of the vehicle Ainstead of the driver. The autonomous drive ECU 50 mainly includes acomputer having a main processor 51, a graphic processor 52, a RAM 53, astorage medium 54, and an input/output interface 55. The autonomousdrive ECU 50 can execute the autonomous drive program, the drive modeswitch program, and the like stored in the storage medium 54 using theprocessors 51 and 52. The autonomous drive ECU 50 has a travelenvironment recognition unit 61, a travel plan generation unit 62, adrive mode switch control unit 63, an ECU communication unit 64, and anHCU communication unit 65 as functional blocks related to the autonomousdrive based on the autonomous drive program and the drive mode switchprogram.

The travel environment recognition unit 61 recognizes the travelenvironment of the vehicle A by combining the position informationacquired from the GNSS receiver 71, the map data acquired from the mapdatabase 72, the detected object information acquired from eachautonomous sensor, and the like. The travel environment recognition unit61 recognizes the shape and movement state of the object around thevehicle A, particularly within the detection range of each autonomoussensor, based on the integration result of the detected objectinformation and combines the shape and movement state of the object withthe position information and the map data. With this configuration, thetravel environment recognition unit 61 generates a virtual space thatreproduces the actual travel environment in three dimensions.

The travel plan generation unit 62 generates a travel plan forautonomous travel of the vehicle A by the autonomous drive functionbased on the travel environment recognized by the travel environmentrecognition unit 61. As a travel plan, a long and medium term travelplan and a short term travel plan are generated. In the long and mediumterm travel plan, a route for directing the vehicle A to the destinationset by the driver is defined. The schedule of planned drive mode switchfrom the autonomous drive function to the driver is mainly set based onthe long and medium term travel plan. In the short term travel plan, aplanned travel route for realizing a travel according to the long andmedium term travel plan is defined by using the virtual space around thevehicle A generated by the travel environment recognition unit 61.Specifically, a steering for lane keeping and lane change,acceleration/deceleration for speed adjustment, sudden braking forcollision avoidance, and the like are determined and executed based onthe short term travel plan.

The drive mode switch control unit 63 controls the switch of the controlright related to the drive operation between the autonomous drivefunction and the driver. The drive mode switch control unit 63 startsthe operation of the autonomous drive function by detecting the switchoperation to the autonomous drive by the driver in the area where theautonomous drive can be executed. The drive mode switch control unit 63switches from the autonomous drive to the manual drive of the driver asplanned before the end of the area capable of autonomous drive ends bythe reference to the long and middle term travel plan. Even when thetravel environment recognition unit 61 accidentally or suddenly hasdifficulty in recognizing the travel environment, so that the travelplan generation unit 62 has difficulty in generating the short termtravel plan, the drive mode switch control unit 63 is capable ofswitching from the autonomous drive to the manual drive.

The ECU communication unit 64 executes an output processing of theinformation to the vehicle control ECU 80 and an acquisition processingof the information from the vehicle control ECU 80. Specifically, theECU communication unit 64 generates the vehicle control information forinstructing acceleration/deceleration and steering according to theplanned travel route defined by the travel plan generation unit 62, andsequentially outputs the vehicle control information together with thedrive state information (described later) indicating the operation stateof the autonomous drive to the vehicle control ECU 80. The ECUcommunication unit 64 is capable of correcting the content of thevehicle control information by sequentially acquiring the stateinformation indicating the control state of the vehicle actuator group90 from the vehicle control ECU 80.

In addition, the ECU communication unit 64 has an operation informationacquisition block 64 a as a sub functional block. The operationinformation acquisition block 64 a acquires signals output from theaccelerator position sensor 44, the brake operation amount sensor 45,the steering angle sensor 46, and the detection switch 47 as theoperation information related to the drive operation input by thedriver. The operation information is provided to the drive mode switchcontrol unit 63, and is used at the time of the drive mode switch fromthe autonomous drive function to the driver.

The HCU communication unit 65 executes an output processing of theinformation to the HCU 20 and an acquisition processing of theinformation from the HCU 20. The HCU communication unit 65 has a drivemode switch request block 65 a as a sub functional block. The drive modeswitch request block 65 a generates the switch request information forrequesting the drive mode to switch from the autonomous drive functionto the driver based on the drive mode switch schedule generated by thedrive mode switch control unit 63, and outputs the switch requestinformation to the HCU 20. The drive mode switch request block 65 arequests the driver to switch the drive mode by controlling thenotification device 10 in cooperation with the HCU 20.

Next, the details of the drive mode switch control by the drive modeswitch control unit 63 described above will be further described. Thedrive mode switch control unit 63 includes a drive state switch block 63a and an operation detection block 63 b as sub functional blocks thatcontrol switching from the autonomous drive to the manual drive. First,the functions of these sub functional blocks will be described based onFIG. 1 and FIG. 3.

The drive state switch block 63 a switches the drive mode of the vehicleA among a plurality of predetermined drive modes (see FIG. 3) by thecontrol of transitioning the operation state of the autonomous drivefunction. The plurality of predetermined drive modes switched by thedrive state switch block 63 a includes at least a coordination drivemode and an autonomous retraction mode in addition to the manual drivemode and the normal autonomous drive mode. The drive mode currently setby the drive state switch block 63 a is notified to the informationacquisition unit 31 of the HCU 20 and the drive information acquisitionunit 80 a of the vehicle control ECU 80 as drive state information.

In the manual drive mode, the autonomous drive function is stopped, andthe driver controls the travel of the vehicle A. The vehicle control ECU80 that acquires the drive state information indicative of being in themanual drive mode causes the actuator control unit 80 b to generate thecontrol signal according to the operation information acquired from eachof the sensors 44 to 46, and transmits the control signal to the vehicleactuator group 90.

In the autonomous drive mode, the autonomous drive function controls thetravel of the vehicle A. The vehicle control ECU 80 that acquires thedrive state information indicative of being in the autonomous drive modecauses the actuator control unit 80 b to generate the control signalaccording to the vehicle control information acquired from theautonomous drive ECU 50, and transmits the control signal to the vehicleactuator group 90.

The coordination drive mode is a specific one of the autonomous drivemode. Thus, in the coordination drive mode, the autonomous drivefunction is operating. In the coordination drive mode, the travel of thevehicle A is controlled by coordinating the control by the autonomousdrive function and the drive operation by the driver. The vehiclecontrol ECU 80 that acquires the drive state information indicative ofbeing in the coordination drive mode generates the control signal basedon the operation information acquired from each of the sensors 44 to 46and the vehicle control information acquired from the autonomous driveECU 50, and outputs the control signal to the vehicle actuator group 90.

Specifically, when the drive force indicated by the drive stateinformation and the drive force indicated by the operation informationare different from each other, the actuator control unit 80 b generatesthe control signal based on the larger drive force of the two driveforces. Similarly, when the braking force indicated by the drive stateinformation and the braking force indicated by the operation informationare different from each other, the actuator control unit 80 b generatesthe control signal based on the larger braking force of the two brakingforces. In addition, when the steering target value indicated by thedrive state information and the actual steering angle indicated by theoperation information are different from each other, the actuatorcontrol unit 80 b outputs the control signal that causes the torque ofthe steering actuator to increase or decrease so that the steeringtarget value indicated by the drive state information approaches theactual steering angle.

The autonomous retraction mode is another one of the autonomous drivemode. Thus, in the cooperative drive mode, the autonomous drive functionis operating. The autonomous retraction mode is executed when thetransfer of control right from the autonomous drive function to thedriver is not desired. The vehicle A in the autonomous retraction modeautomatically travels to the stop position searched by the autonomousdrive ECU 50, and stops at the stop position. The vehicle control ECU 80that acquires the drive state information indicative of being in theautonomous retraction mode basically ignores the operation informationacquired from each of the sensors 44 to 46, and outputs the controlsignal based on the vehicle control information acquired from theautonomous drive ECU 50.

In the vehicle A on which the autonomous drive function is operating,the operation detection block 63 b detects the drive operation of thedriver related to a handover and an override of the control right basedon the operation information acquired by the operation informationacquisition block 64 a. The handover represents one of the drive modeswitches in which the control right is transferred to the driver. In thehandover, when the autonomous drive ECU 50 determines that theautonomous drive cannot continue, the autonomous drive ECU 50 requeststhe driver to switch the driving and the driver performs the driveoperation in response to the request. On the other hand, the overriderepresents one of the drive mode switches in which the control right istransferred to the driver. In the override, while the vehicle A istravel by the autonomous drive function, the driver performs the driveoperation by own intention. The handover is the transfer from theautonomous drive function to the driver based on the determination ofthe system. The override is the transfer from the autonomous drivefunction to the driver based on the determination of the driver.

When the drive mode is not in the manual mode, that is, when the drivemode is in the autonomous drive mode or in the coordination drive modein which the autonomous drive function is capable of intervening in thedrive operation, the operation detection block 63 b detects a firstoperation or a second operation which is the drive operation by thedriver. The operation detection block 63 b stores, for each operationtarget, an operation amount threshold value and a time threshold valuethat respectively define the operation amount and the operationcontinuation time for performing the presence determination of the firstoperation or the second operation. The operation detection block 63 bdetects, as the first operation or the second operation, the driveoperation that exceeds both the operation amount threshold value and thetime threshold value based on the operation information.

The operation detection block 63 b detects, as the first operation, thedrive operation that is reflexively performed by the driver in responseto an event that may interfere with the travel of the vehicle A. Thefirst operation is a drive operation that is estimated to have beeninputted by the driver in a hurry. On the other hand, a drive operationperformed after the first operation and different from the firstoperation is detected as the second operation. The second operation is adrive operation estimated to be performed after the driver recovers theintention for driving.

Specifically, it is considered that it takes approximately 2.5 secondsfor the driver to recover the intention to drive from the occurrence ofthe event. On the other hand, it is considered that the reflexive driveoperation is performed within approximately 2.0 seconds from theoccurrence of the event. Therefore, in the operation detection block 63b, a value of approximately 0.5 seconds is set as a time for recovery ofthe driver's intention (intention recovery time). The operationdetection block 63 b detects, as the second operation, the driveoperation performed in approximately 0.5 seconds after the detectiondetermination of the first operation.

The operation targets to which the first operation and the secondoperation are input may be the same or different. As an example, theoperation detection block 63 b may detect a drive operation of steppingon the brake pedal 15 as the first operation and may detect a driveoperation of steering the steering wheel 16 as the second operation. Asdescribed above, the operation detection block 63 b is capable ofdetecting, as the second operation, a drive operation on an operationtarget other than the operation target to which the first operation hasbeen input.

As another example, the operation detection block 63 b may detect adrive operation of strongly depressing on the brake pedal 15 as thefirst operation and may detect a drive operation in which the depressionforce of the brake pedal 15 is adjusted as the second operation. Asdescribed above, the operation detection block 63 b is capable ofdetecting the drive operation, as the second operation, which is inputto the operation target to which the first operation is input and theoperation amount of which is smaller than the operation amount of thefirst operation.

Next, the correlation of the transition of the drive mode by the drivestate switch block 63 a will be further described based on FIGS. 3 to 5,with reference to FIG. 1.

The drive state switch block 63 a switches the drive mode from themanual drive mode to the normal autonomous drive mode in response to aninput of a switch for instructing the start of autonomous drive providedin an operation system such as the steering switch. As shown in FIG. 3and FIG. 4, in the autonomous drive mode, for example, when the drivernotices a falling object or the like in front to be avoided (time pointt1), the drive operation that exceeds the operation amount thresholdvalue and the time threshold value is input by the driver (time pointt2). Based on the detection of the first operation, the drive stateswitch block 63 a switches the drive mode from the autonomous drive modeto the coordination drive mode.

In the coordination drive mode, when the driver input an additionaldrive operation after the first operation continues beyond the referencevalue, the drive operation is detected by the operation detection block63 b (time point t3). Based on the detection of the second operation,the drive state switch block 63 a switches the drive mode from thecoordination drive mode to the manual drive mode. In the firstembodiment, when the second operation detection is determined, theswitching of the drive state from the coordination drive mode to themanual drive mode is immediately started. As described above, theoverride by the driver is completed.

There may be no request for drive mode switch shown in FIG. 3 and apredetermined restart standby period (for example, approximately 3seconds) may have passed without detecting the second operation afterthe switching to the coordination drive based on the detectiondetermination of the first operation. In this time, the drive stateswitch block 63 a switches the drive mode from the coordination drivemode to the autonomous drive mode. With the above-described control, thevehicle A resumes the travel by the autonomous drive function evenwithout the driver's special operation. With the transition of the drivemode, when being in the autonomous drive and trying to overtake a largevehicle travel in an adjacent lane, the vehicle A is capable oftemporarily moving farther from the large vehicle in the lane by thesteering operation without canceling the autonomous drive.

As shown in FIGS. 3 and 5, in the autonomous drive mode, when it isdetermined that the continuation of the autonomous drive is impossible,the autonomous drive transitions to the mode that executes a drive modeswitch request (time point t1). When the driver notices such a drivemode switch request (time point t2), a drive operation that exceeds theoperation amount threshold value and the time threshold value is input.Based on the detection of the first operation, the drive state switchblock 63 a switches to the coordination drive mode (time point t3).

In the coordination drive mode, when the driver input the additionaldrive operation after the first operation continues beyond the referencevalue, the drive operation is detected (time point t4). Based on thedetection of the second operation, the drive state switch block 63 astops the drive mode switch request and switches from the coordinationdrive mode to the manual drive mode. The switch of the drive state fromthe coordination drive mode to the manual drive mode is triggered by thedetermination that the second operation is detected, and immediatelystarts without a waiting time. As described above, the handover by thedriver is completed.

As shown in FIG. 3, when a predetermined request execution timepreliminary has elapsed without the detection of the second operationafter the transition to the coordination drive mode in response to thedrive mode switch request, the drive state switch block 63 a switchesfrom the coordination drive mode to the autonomous retraction mode.Similarly, when the predetermined request execution time has elapsedwithout the detection of any drive operation after the execution of thedrive mode switch request, the drive state switch block 63 a switches tothe autonomous retraction mode. With this configuration, the vehicle Asequentially starts the search for the stop position and the travel tothe stop position by the coordination control of the autonomous driveECU 50 and the vehicle control ECU 80. The above-described controleffectively functions when the driver has difficulty in driving. Therequest execution time is set so that the vehicle A does not go out ofthe autonomous drive area without switching to the manual drive mode.For example, the request execution time is set to approximately 4seconds.

The details of the drive mode switch control processing executed by theautonomous drive ECU 50 in order to realize the above-described overrideand handover will be described based on FIGS. 6 and 7, with reference toFIG. 1. The drive mode switch control processing shown in FIGS. 6 and 7is started by the drive mode switch control unit 63 based on theswitching from the manual drive mode to the autonomous drive mode.

According to the drive mode switch control processing shown in FIG. 6,the above-described handover is realized. At S101, the drive switchcontrol unit 63 acquires the operation information related to the driveoperation input by the driver, and detects the first operation based onthe acquired operation information. When the drive switch control unit63 detects the first operation at S101, the processing proceeds to S102.On the other hand, when the drive switch control unit 63 cannot detectthe first operation at S101, the drive switch control unit 63 continuesthe detection determination at S101. When the vehicle A is not in themanual operation mode, the drive switch control unit 63 continuouslyperforms the detection determination at S101.

At S102, the drive switch control unit 63 starts counting of a timer,which measures the continuation period of the first operation, in orderto measure an elapsed time et1 from the time point t2 (see FIG. 4) atwhich the first operation is detected, and the processing proceeds toS103. At S103, the drive switch control unit 63 switches the drive modeof the vehicle A from the autonomous drive mode to the coordinationdrive mode (see time point t2 in FIG. 4) based on the detectiondetermination of the first operation at S101, and the processingproceeds to S104 (see time point t2 in FIG. 4).

At S104, the drive switch control unit 63 determines whether the elapsedtime et1 of the timer at which the drive switch control unit 63 startscounting at S102 exceeds the reference value. As the reference value,0.5 seconds which is the above-described intention recovery time isapplied as an example. At S104, the drive switch control unit 63 repeatsthe determination whether the elapsed time et1 exceeds the referencevalue. When the elapsed time et1 exceeds the reference value, theprocessing proceeds to S105.

At S105, the drive switch control unit 63 detects the second operationof the drive based on the operation information. When the drive switchcontrol unit 63 detects the second operation at S105, the processingproceeds to S106. On the other hand, when the drive switch control unit63 cannot detect the second operation, the drive switch control unit 63continues the detection determination at S105. At S106, the drive modeswitch control unit 63 switches the drive mode of the vehicle A from thecoordination drive mode to the manual drive mode (see time point t3 inFIG. 4) based on the detection determination of the second operation atS105, and the drive switch control processing is terminated.

According to the drive mode switch control processing shown in FIG. 7,the above-described override is realized. At S111, the drive mode switchcontrol unit 63 determines whether the time point for requesting thedrive mode switch to the driver comes based on the long and medium termtravel plan. The determination at S111 is repeated until the time pointfor requesting the drive mode switch comes. When the drive mode switchcontrol unit 63 determines that the time point for requesting the drivemode switch comes at S111, the processing proceeds to S112. At S112, thedrive mode switch control unit 63 starts requesting the drive modeswitch (see time point t1 in FIG. 5), the processing proceeds to S113.

At S113, the drive switch control unit 63 executes the detectiondetermination of the first operation similarly to S101 (see FIG. 6). Inresponse to the detection of the first operation, the processingproceeds to S114. At S114, the drive switch control unit 63 startscounting of the timer in order to measure the elapsed time et1 from thetime point t3 (see FIG. 5) at which the first operation is detected, andthe processing proceeds to S115. At S115, the drive switch control unit63 switches the drive mode of the vehicle A from the autonomous drivemode to the coordination drive mode (see time point t3 in FIG. 5) basedon the detection determination of the first operation at S114, and theprocessing proceeds to S116.

At S116, the drive switch control unit 63 determines whether the elapsedtime et1 of the timer exceeds the reference value (for example, 0.5seconds) similarly to S104 (see FIG. 6). In response that the elapsedtime et1 exceeds the reference value, the processing proceeds to S117.At S117, the drive switch control unit 63 executes the detectiondetermination of the second operation similarly to S105 (see FIG. 6). Inresponse to the detection of the second operation, the processingproceeds to S118. At S118, the drive mode switch control unit 63switches the drive mode of the vehicle A from the coordination drivemode to the manual drive mode (see time point t4 in FIG. 5) based on thedetection determination of the second operation at S117, and the drivemode switch control processing is terminated.

In the first embodiment described above, not when the input of the firstoperation is determined but when the input of the second operation afterthe detection of the first operation is determined, the coordinationdrive mode is switched to the manual drive mode. With thisconfiguration, the switch to the manual drive mode can be prevented whenthe reflexive drive operation or the continuous drive operation withoutrecover of the intention to drive is performed. On the other hand, whenthe driver performs the second operation after recovering the intentionto drive, the switch to the manual drive mode is executed based on theinput determination of the second operation. Therefore, the autonomousdrive ECU 50 can switch to the manual drive mode after the driverbecomes in a state that can reflect the intention on the driveoperation.

In addition, in the first embodiment, the switch of the drive state fromthe coordination drive mode to the manual drive mode is started atsubstantially the same time point as the detection of the secondoperation based on the detection determination of the second operation.With the set of such switch start time point, the autonomous drive ECU50 can quickly return the control of the drive operation to the driverwho recovers the intention to drive.

The operation detection block 63 b of the first embodiment can detectthe drive operation, as the second operation, which is input to the sameoperation target having been input in the first operation and theoperation amount of which is smaller than the operation amount of thefirst operation. In general, the driver notices that the operationamount of the drive operation (first operation) input in response to theevent that has occurred is excessive, and performs the drive operationfor adjusting the operation amount to be smaller. The driver whoperforms the drive operation to adjust such an operation amount isrecovered to the state in which the intention can be reflected in thedrive operation. Therefore, when the drive operation that reduces theoperation amount is detected as the second operation, the control rightof the drive operation can be reliably passed to the driver in the statein which the intention can be reflected in the drive operation.

The operation detection block 63 b of the first embodiment can detect,as the second operation, the drive operation to the operation targetother than the operation target to which the first operation has beeninput. When performing the drive operations to the plurality of theoperation targets, the driver is highly likely to have already recoveredthe intention to the drive operations. Therefore, when the driveoperation that is different from the drive operation in the firstoperation is detected as the second operation, the drive mode switchcontrol unit 63 can reliably pass the control right of the driveoperation to the driver who can reflect the intention of the driveoperation.

The operation detection block 63 b of the first embodiment detects, asthe second operation, the drive operation performed after the intentionrecovery time has elapsed since the first operation of the detectiondetermination is executed. As described above, with the differencebetween the detection time points of the first operation and the secondoperation, the unintended operation input of the reflexive firstoperation can be avoided to be detected as the second operation. Then,the certainty that only the intended drive operation is detected as thesecond operation is improved.

In the first embodiment, when no intentional drive operation is inputafter the drive mode switch is requested, the drive mode is not switchedto the manual drive mode but to the autonomous retraction mode. With thecontrol described above, the drive mode switch to the driver who has notrecovered the intention to the drive operation can be reliably avoided.

When the drive mode switch request is not performed, the autonomousdrive ECU 50 can continue the autonomous drive. There may be no requestfor drive mode switch. In this case, when the second operation is notdetected after the switch to the coordination drive mode, the drive modemay be returned to the autonomous drive mode. The control describedabove can prevents the control right from being passed to the driver whohas no intention of the drive operation.

In the first embodiment, the autonomous drive ECU 50 corresponds to a“drive mode switch control device”. The main processor 51 and thegraphic processor 52 correspond to a “processing unit”. The drive stateswitch block 63 a corresponds to a “drive state switch unit”. Theoperation detection block 63 b corresponds to an “operation detectionunit”. The operation information acquisition block 64 a corresponds toan “operation information acquisition unit”. The drive mode switchrequest block 65 a corresponds to an “drive mode switch request unit”.The autonomous drive mode corresponds to an “autonomous drive state”.The manual operation mode corresponds to a “manual operation state”. Thecoordination drive mode corresponds to a “coordination drive state”. Theautonomous retraction mode corresponds to an “autonomous evacuationstate”.

Second Embodiment

A second embodiment of the present disclosure shown in FIGS. 8 to 11 isa modification of the first embodiment. The second operation maycontinue beyond a predetermined switch standby time tde after thedetection determination of the second operation is executed. In thiscase, the drive state switch block 63 a (see FIG. 1) according to thesecond embodiment starts switching the drive mode from the coordinationdrive mode to the manual drive mode. The switch standby time tde may beset to substantially the same time as the intention recovery time tre,for example, set to approximately 0.5 seconds.

The transition of switching of the drive mode at the time of theoverride and the detail of the drive mode switch control processing willbe sequentially described based on FIGS. 8 and 9 with reference to FIG.1.

In the time chart shown in FIG. 8, the transition by the time point t3is substantially the same as in the first embodiment (see FIG. 4). Whenthe driver notices at the time point t1 and inputs the drive operation,the drive operation is detected as the first operation at the time pointt2. Based on the detection determination of the first operation, thedrive state switch block 63 a switches the drive mode from theautonomous drive mode to the coordination drive mode.

At the time point t3 after the first operation continues beyond theintention recovery time tre, which is the reference value, from theswitching to the coordination drive mode, the drive operation isdetected as the second operation in response to the input of the driveoperation by the driver. At the time point t4 at which the secondoperation exceeds the reference value, the drive state switch block 63 aswitches the drive mode from the coordination drive mode to the manualdrive mode. The above-described switch standby time tde (approximately0.5 seconds) is used as an example of the reference value to be comparedwith the continuation period of the second operation.

S201 to S205 of the flowchart shown in FIG. 9 are substantially the sameas S101 to S105 (see FIG. 6) of the first embodiment. At S203, theswitching to the coordination drive mode is executed. At S206 after thedetection of the second operation at S205, the drive switch control unit63 starts counting of the timer, which measures the continuation periodof the second operation, in order to measure an elapsed time et2 fromthe time point t3 (see FIG. 8) at which the second operation isdetected, and the processing proceeds to S207.

At S207, the drive switch control unit 63 determines whether the elapsedtime et2 of the timer that has started counting at S206 exceeds thereference value, which is provided by the switch standby time tde. AtS207, the drive switch control unit 63 repeats the determination whetherthe elapsed time et2 exceeds the reference value. When the elapsed timeet2 exceeds the reference value, the processing proceeds to S208. AtS208, the drive switch control unit 63 switches the drive mode of thevehicle A from the coordination drive mode to the manual drive mode (seetime point t4 in FIG. 8), and the drive mode switch control processingis terminated.

The transition of switching of the drive mode at the time of handoverand the detail of the drive mode switch control processing will besequentially described based on FIGS. 10 and 11 with reference to FIG.1.

In the time chart shown in FIG. 10, the transition by the time point t3is substantially the same as in the first embodiment (see FIG. 5). Thedrive mode switch to the driver may be requested at the time point t1due to the transition to the mode for performing the drive mode switchrequest. In this case, after the driver's notice occurs at the timepoint t2, the driver inputs the drive operation. The drive operation isdetected at the time point t3, and the drive state switch block 63 aswitches to the coordination drive mode.

At the time point t4 after the first operation continues beyond theintention recovery time tre, which is the reference value, from theswitching to the coordination drive mode, the drive operation isdetected as the second operation in response to the input of the driveoperation by the driver. At the time point t5 at which the secondoperation exceeds the switch standby time tde, which is the referencevalue, the drive state switch block 63 a switches the drive mode fromthe coordination drive mode to the manual drive mode.

S211 to S217 of the flowchart shown in FIG. 11 are substantially thesame as S111 to S117 (see FIG. 7) of the first embodiment. At S215, theswitching to the coordination drive mode is executed. At S218 after thedetection of the second operation at S217, the drive switch control unit63 starts counting of a timer in order to measure an elapsed time et2from the time point t4 (see FIG. 10) at which the second operation isdetected, and the processing proceeds to S219.

At S219, the drive switch control unit 63 determines whether the elapsedtime et2 of the timer that has started counting at S218 exceeds thereference value, which is provided by the switch standby time tde. AtS219, the drive switch control unit 63 repeats the determination whetherthe elapsed time et2 exceeds the reference value. When the elapsed timeet2 exceeds the reference value, the processing proceeds to S220. AtS220, the drive mode switch control unit 63 switches the drive mode ofthe vehicle A from the coordination drive mode to the manual drive mode(see time point t5 at FIG. 10), and the drive mode switch controlprocessing is terminated.

In the second embodiment described above, the same effects as in thefirst embodiment can be obtained. After the driver becomes in a statethat can reflect the intention on the drive operation, the switching tothe manual drive mode, that is, the cancel of the autonomous drivefunction can be executed.

In addition, in the second embodiment, the switching of the drive statefrom the coordination drive mode to the manual drive mode is started atthe time point when the second operation continues beyond the switchstandby time tde. In the above-described configuration, the switching tothe manual drive mode starts not immediately after the detection of thesecond operation but at the elapse of the switch standby time tde. Thus,for example, even when the driver touches another operation targetwithout intention as the input of the first operation, the drive modeswitch is prevented. Thus, the autonomous drive ECU 50 can reliably passthe control right of the drive operation to the driver in a state inwhich the intention can be reflected in the drive operation.

Third Embodiment

A third embodiment of the present disclosure shown in FIGS. 12 to 14 isanother modification of the first embodiment. The autonomous drivefunction mounted on the vehicle A of the third embodiment is a functionof semi-autonomous drive realized by a so-called advanced drive supportsystem.

The advanced drive support system referred to the third embodiment is asystem on the premise that the driver can drive at any time during theoperation of the autonomous drive function by the system. When theadvanced drive support system determines that the drive support cannotbe continued, the drive state transitions to the manual drive modewithout a drive mode switch request as in the above-describedembodiment.

The advanced drive support system can execute acceleration, steering, orbraking of the vehicle A. In the advanced drive support system, therequest for drive mode switch based on the long and medium term travelplan is not executed. The function of the drive mode switch controldevice in the vehicle A mounted on such an advanced drive support systemis realized by a vehicle control ECU 180 shown in FIG. 12.

The vehicle control ECU 180 has a part of the functions of theautonomous drive ECU 50 (see FIG. 1) of the first embodiment, andenables the semi-autonomous drive for the vehicle A. In the vehiclecontrol ECU 180, a drive information acquisition unit 180 a, an ADASfunction unit 161, and a drive mode switch control unit 163 areconstructed as functional blocks, and the actuator control unit 80 b andthe HCU communication unit 65, each of which is substantially the sameas the first embodiment, are also constructed as functional blocks.

The drive information acquisition unit 180 a has the function of theoperation information acquisition block 64 a (see FIG. 1) of the firstembodiment. The drive information acquisition unit 180 a acquires theoperation information output from each of the sensors 44 to 46 and thedetection switch 47. The operation information is provided to the drivemode switch control unit 163, and is used at the time of the drive modeswitch from the autonomous drive function to the driver.

An ADAS (Advanced drive Assistant System) functional unit 161 has atarget recognition block 161 a, an ACC (Adaptive Cruise Control)function block 161 b, and an LTC (Lane Trace Control) function block 161c as sub functional blocks.

The target recognition block 161 a detects the relative position and thelike of moving object and stationary object in the travel direction byintegrating detected object information acquired from the camera unit73, the lidar 74, and the millimeter wave radar 75. For example, thetarget recognition block 161 a can recognize a preceding vehicle, a lanemarking, or the like.

The ACC function block 161 b controls the travel speed of the vehicle Aby adjusting the drive force and the braking force in cooperation withthe actuator control unit 80 b based on the relative positioninformation of the moving object or the stationary object recognized bythe target recognition block 161 a. Specifically, the ACC function block161 b causes the vehicle A to cruise at a target speed set by the driverwhen a leading vehicle is not detected. When a leading vehicle isdetected, the ACC function block 161 b causes the vehicle A to followthe preceding vehicle while maintaining the distance between thepreceding vehicle.

The LTC function block 161 c controls the steering angle of the steeringwheel of the vehicle A by adjusting the steering force in cooperationwith the actuator control unit 80 b based on the shape information ofthe lane marking in the travel direction acquired from the targetrecognition block 161 a. The LTC function block 161 c causes the vehicleA to travel so as to follow the lane in the travel.

The drive mode switch control unit 163 determines the intention of thedriver for the override and stops the operation of the ADAS functionunit 161 that realizes the advanced drive support system. The drive modeswitch control unit 163 includes the operation detection block 63 b andthe operation state switch block 63 a as in the first embodiment. Theoperation detection block 63 b detects the drive operation of the driverrelated to the override based on the operation information acquired bythe drive information acquisition unit 180 a.

The drive state switch block 63 a switches the drive mode among themanual drive mode, an advanced drive support mode, and the coordinationdrive mode. As shown in FIGS. 12 to 14, the drive state switch block 63a switches the drive mode from the manual drive mode to the advanceddrive support mode in response to an input to a switch for instructingthe operation of ACC or LTC provided in the operation system such as asteering switch (see FIG. 13). In the advanced drive support mode, atleast one of the ACC function block 161 b and the LTC function block 161c functions.

In the advanced drive support mode, when the driver notices (see timepoint t1 in FIG. 14), the driver inputs a drive operation (see timepoint t2 in FIG. 14). Based on the detection of the first operation, thedrive state switch block 63 a switches the drive mode from the advanceddrive support mode to the coordination drive mode.

In the coordination drive mode, when the driver inputs the additionaldrive operation after the elapsed time et1 exceeds the intentionrecovery time tre due to the continuation of the first operation, theadditional drive operation is detected as the second operation (see timepoint t3 in FIG. 14). Based on the detection of the second operation,the drive state switch block 63 a switches the drive mode from thecoordination drive mode to the manual drive mode. As described above,the override by the driver is completed. The override of the thirdembodiment can be realized by the drive mode switch control processing(see FIG. 7) substantially the same as the override of the firstembodiment.

On the other hand, a predetermined restart standby period passes withoutthe detection of the second operation after the switching to thecoordination drive, the drive mode switch control unit 163 returns thedrive mode from the coordination drive mode to the advanced drivesupport mode.

When determining that the continuation of the autonomous drive in theadvanced drive support mode is impossible, the ADAS function unit 161automatically stops the ACC function block 161 b and the LTC functionblock 161 c. With the above-described configuration, the operation modeis switched to the manual operation mode.

As described in the third embodiment, the same effects as in the firstembodiment are obtained in the transfer of the authority of the advanceddrive support system, and the configuration can switch to the manualdrive mode after the driver becomes in the state that can reflect theintention in the drive operation. In the third embodiment, the vehiclecontrol ECU 180 corresponds to the “drive mode switch control device”,the drive information acquisition unit 80 a corresponds to the“operation information acquisition unit”, and the advanced drive supportmode corresponds to the “autonomous drive state”.

Fourth Embodiment

A fourth embodiment of the present disclosure shown in FIG. 15 is amodification of the third embodiment. When the second operation maycontinue beyond a predetermined switch standby time tde, the drive stateswitch block 63 a (see FIG. 12) according to the fourth embodimentstarts switching from the coordination drive mode to the manual drivemode, similarly to the second embodiment.

The transition in the override according to the fourth embodiment issubstantially the same as the transition in the override according tothe second embodiment (see FIG. 5). Specifically, when the drivernotices at the time point t1 and a drive operation is input, the driveoperation is detected as a first operation at the time point t2. Basedon the detection determination of the first operation, the drive stateswitch block 63 a switches the drive mode from the advanced drivesupport mode to the coordination drive mode.

At the time point t3 after the first operation continues beyond theintention recovery time tre (approximately 0.5 seconds) from theswitching to the coordination drive mode, the drive operation isdetected as the second operation in response to the input of the driveoperation by the driver. At the time point t4 at which the secondoperation continues beyond the switch standby time tde (approximately0.5 seconds), the drive state switch block 63 a switches the drive modefrom the coordination drive mode to the manual drive mode. As describedabove, the override by the driver is completed. The override of thefourth embodiment can be realized by the drive mode switch controlprocessing (see FIG. 9) substantially the same as the second embodiment.

As described in the third embodiment, the same effects as in the thirdembodiment are obtained, and the configuration can switch to the manualdrive mode after the driver becomes in the state that can reflect theintention in the drive operation.

Other Embodiments

In the above-described embodiment, it is desirable that the operationtarget of the first operation to be the trigger of switching to thecoordination drive mode is limited to the accelerator pedal, the brakepedal, and the steering wheel. On the other hand, the operation targetof the second operation to be the trigger of switching to the manualoperation mode is not limited to the operation target for the firstoperation, and may include the turn signal lever, the shift lever, theshift paddle, or the like.

The drive operation detected as the second operation may be limited tothe drive operation input to an operation target different from theoperation target input for the first operation. That is, a driveoperation that adjusts the depression force of the accelerator pedal orthe brake pedal may not be detected as the second operation. Whether toprovide the switch standby time may be set according to the type of theoperation target to which the second operation is input.

In the above-described embodiment, the drive operation detected as thesecond operation is limited to the drive operation after the input ofthe first operation continues for equal to or more than the intentionrecovery time (approximately 0.5 seconds). The specific length of theintention recovery time may be adjusted accordingly. In addition, theoperation detection block may detect, as the second operation, the driveoperation after a predetermined intention recovery time (for example,2.5 seconds) has elapsed from the start time point of the drive modeswitch request (see time point t1 in FIG. 5).

In the first embodiment, the switching to the manual operation mode isimmediately started with the detection of the second operation as thetrigger. Alternatively, a predetermined delay time may be set betweenthe detection of the second operation and the start of the switching.The length of such delay time may be changed as appropriate according tothe travel environment, the travel state, or the like.

In the above-described embodiment, when the second operation is notdetected after the transition to the coordination drive mode, the drivemode is returned to the autonomous drive mode or the advanced drivesupport system mode. Alternatively, the coordination drive mode may becontinued until the detection of the second operation.

In the first embodiment, when the drive operation is not detected afterthe drive mode switch is requested, the drive mode is forcibly switchedto the autonomous retraction mode. Alternatively, the switching to theautonomous retraction mode may not be performed. For example, thevehicle A may be gradually stopped without searching for the stopposition. Moreover, the notification device which requests drive modeswitch is not limited to the display device and the speaker device. Thenotification device may be constituted by a tactile sense presentationdevice.

As described in the above embodiment, the control, which employs thesecond operation for the trigger of switching from the coordinationdrive mode to the manual drive mode, can be applied to the low-levelautonomous drive and high-level autonomous drive. In the low-levelautonomous drive, the driver is obliged to monitor the drive even thoughthe autonomous drive is in progress. In the high-level autonomous drive,the drive monitoring duty is not imposed to the driver.

The function of the drive mode switch control device may be realized bya configuration different from the configuration of the above-describedautonomous drive ECU 50 and the vehicle control ECU 180. For example, aprocessing unit provided in the HCU 20 or the like may execute the drivemode switch control method according to the present disclosure.Alternatively, the processing unit, in which the functions of more thantwo of the autonomous drive ECU, the vehicle control ECU, and the HCUare integrated, may execute the drive mode switch control methodaccording to the present disclosure. Alternatively, a plurality ofelectronic control units may cooperate to execute the drive mode switchcontrol method according to the present disclosure. As described above,each function related to drive mode switch may be appropriately realizedby various electronic control units mounted on the vehicle. Variousnon-transitory tangible memory medium (non-transitory tangible storagemedium) such as a flash memory and a hard disk may store the drive modeswitch program or the like which is executed by each processing unit.

The flowcharts or the processing depicted in the flowcharts according tothe present disclosure include a plurality of sections (alternativelyreferred to as steps) each indicated as S101 or the like. Some of thesections may be further divided into a plurality of subsections or maybe appropriately combined to configure a single section. Each of thesesections may also be referred to as a circuit, a device, a module, ormeans.

Each of the plurality of sections or some of the sections combined toeach other can be embodied as (i) a software section combined with ahardware unit (e.g., a computer) or (ii) a hardware section (e.g., anintegrated circuit or a wiring logic circuit) including or excluding afunction of a relevant device. The hardware section may stillalternatively be installed in a microcomputer.

Although the present disclosure has been described in accordance withthe examples, it is understood that the disclosure is not limited tosuch examples or structures. The present disclosure covers variousmodification examples and equivalent arrangements. In addition, whilethe various elements are shown in various combinations andconfigurations, which are exemplary, other combinations andconfigurations, including more, less or only a single element, are alsowithin the spirit and scope of the present disclosure.

1. A drive mode switch control device for a vehicle configured tocontrol a drive mode switch between a driver and an autonomous drivefunction, the vehicle including the autonomous drive function configuredto perform a drive operation instead of the driver, the drive modeswitch control device comprising: an operation information acquisitionunit configured to acquire operation information related to driveoperations input by the driver; a drive state switch unit configured toswitch a drive state among at least an autonomous drive state, a manualdrive state, and a coordination drive state; an operation detection unitconfigured to detect an input of a first driving operation and an inputof a second driving operation based on the operation information, inresponse to the drive state not being in the manual drive state, whereinin the autonomous drive state, a travel of the vehicle is controlled bythe autonomous drive function, in the manual drive state, the travel ofthe vehicle is controlled by the driver, in the coordination drivestate, the travel of the vehicle is controlled by coordinating a controlof the autonomous drive function and the drive operations of the driver,the first driving operation is a driving operation input to a firstoperation target in the vehicle by the driver, the second drivingoperation is a driving operation input to the first operation target bythe driver after the first driving operation is input, the seconddriving operation in magnitude is smaller than the first drivingoperation in magnitude, the drive state switch unit switches the drivestate from the autonomous drive state to the coordination drive state inresponse to detecting the first driving operation, and the drive stateswitch unit switches the drive state from the coordination drive stateto the manual drive state in response to detecting the second drivingoperation.
 2. The drive mode switch control device according to claim 1,wherein the drive state switch unit starts switching the drive statefrom the coordination drive state to the manual drive state when theoperation detection unit detects the second driving operation.
 3. Thedrive mode switch control device according to claim 1, wherein the drivestate switch unit starts switching the drive state from the coordinationdrive state to the manual drive state when the second operationcontinues to exceed a predetermined switch standby time after theoperation detection unit detects the second driving operation.
 4. Thedrive mode switch control device according to claim 1, furthercomprising a drive mode switch request unit configured to request, tothe driver, the drive mode switch from the autonomous drive function tothe driver, wherein: the drive state switch unit switches the drivestate to an autonomous retraction state when the operation detectionunit does not execute the detection determination of the second drivingoperation in a request execution time for the drive mode switch definedby the drive mode switch request unit; and in the autonomous retractionstate, the vehicle is caused to stop at a stop position searched by theautonomous drive function.
 5. The drive mode switch control deviceaccording to claim 7, wherein the drive state switch unit switches thedrive state from the coordination drive state to the autonomous drivestate when the drive mode switch request unit does not request the drivemode switch and a predetermined restart standby period elapses withoutthe detection determination of the second driving operation after thedrive state switch unit switches the drive state to the coordinationdrive state based on the detection determination of the first drivingoperation.
 6. The drive mode switch control device according to claim 1,wherein in response to the vehicle being in the coordination drive stateand a first drive force input from the autonomous drive function beinggreater in magnitude than a second drive force input from the driver,the vehicle is controlled in the coordination drive state with the firstdrive force input, and in response to the vehicle being in thecoordination drive state and the second drive force input from thedriver being greater in magnitude than the first drive force input fromthe autonomous drive function, the driver is allowed to control thevehicle in the coordination drive state with the second drive forceinput.
 7. A drive mode switch control device for a vehicle configured tocontrol a drive mode switch between a driver and an autonomous drivefunction, the vehicle including the autonomous drive function configuredto perform a drive operation instead of the driver, the drive modeswitch control device comprising: an operation information acquisitionunit configured to acquire operation information related to driveoperations input by the driver; a drive state switch unit configured toswitch a drive state among at least an autonomous drive state, a manualdrive state, and a coordination drive state; an operation detection unitconfigured to detect an input of a first driving operation and an inputof a second driving operation based on the operation information, inresponse to the drive state not being in the manual drive state, whereinin the autonomous drive state, a travel of the vehicle is controlled bythe autonomous drive function, in the manual drive state, the travel ofthe vehicle is controlled by the driver, in the coordination drivestate, the travel of the vehicle is controlled by coordinating a controlof the autonomous drive function and the drive operations of the driver,the first driving operation is a driving operation input by the driver,the second driving operation is a driving operation started by thedriver after a predetermined intention recovery time elapses from thefirst driving operation being detected, the drive state switch unitswitches the drive state from the autonomous drive state to thecoordination drive state in response to detecting the first drivingoperation, and the drive state switch unit switches the drive state fromthe coordination drive state to the manual drive state in response todetecting the second driving operation.
 8. A drive mode switch controlmethod for a vehicle configured to control a drive mode switch between adriver and an autonomous drive function, the vehicle including theautonomous drive function configured to perform a drive operationinstead of the driver, the drive mode switch control method beingexecuted by at least one processor, the drive mode switch control methodcomprising: acquiring operation information related to drive operationsinput by the driver; switching a drive state among at least anautonomous drive state, a manual drive state, and a coordination drivestate; detecting an input of a first driving operation and an input of asecond driving operation based on the operation information, in responseto the drive state not being in the manual drive state; switching fromthe autonomous drive state to the coordination drive state in responseto detecting the first driving operation; and switching from thecoordination drive state to the manual drive state in response todetecting the second driving operation, wherein in the autonomous drivestate, a travel of the vehicle is controlled by the autonomous drivefunction, in the manual drive state, the travel of the vehicle iscontrolled by the driver, in the coordination drive state, the travel ofthe vehicle is controlled by coordinating a control of the autonomousdrive function and the drive operations of the driver, the first drivingoperation is a driving operation input to a first operation target inthe vehicle by the driver, the second driving operation is a drivingoperation input to the first operation target by the driver after thefirst driving operation is input, and the second driving operation inmagnitude is smaller than the first driving operation in magnitude.
 9. Adrive mode switch control method for a vehicle configured to control adrive mode switch between a driver and an autonomous drive function, thevehicle including the autonomous drive function configured to perform adrive operation instead of the driver, the drive mode switch controlmethod being executed by at least one processor, the drive mode switchcontrol method comprising: acquiring operation information related todrive operations input by the driver; switching a drive state among atleast an autonomous drive state, a manual drive state, and acoordination drive state; detecting an input of a first drivingoperation and an input of a second driving operation based on theoperation information, in response to the drive state not being in themanual drive state; switching from the autonomous drive state to thecoordination drive state in response to detecting the first drivingoperation; and switching from the coordination drive state to the manualdrive state in response to detecting the second driving operation,wherein in the autonomous drive state, a travel of the vehicle iscontrolled by the autonomous drive function, in the manual drive state,the travel of the vehicle is controlled by the driver, in thecoordination drive state, the travel of the vehicle is controlled bycoordinating a control of the autonomous drive function and the driveoperations of the driver, the first driving operation is a drivingoperation input by the driver, and the second driving operation is adriving operation started by the driver after a predetermined intentionrecovery time elapses from the first driving operation being detected.